This function returns elapsed seconds as float. Thus the clock that starts with an application will lose its milliseconds in 27 hours. For stand-alone game it may be ok. No one would play the whole day and night through.
But for some applications it may not be suitable. For my engine's task scheduler I need a clock with millisecond's precision and unsigned long capacity. Why not to extend sf::Clock with an appropriate function that returns elapsed milliseconds as unsigned long like Ogre's getMilliseconds()? The lack of this function makes developers implement their own timers or use 3d-party's ones.
